Recent years, in an active matrix type liquid crystal display device equipped with a switching element in each pixel, a structure using lateral electric field, such as IPS (In-Plane Switching) mode and FFS (Fringe Field Switching) mode is put to practical use. The liquid crystal display device using the lateral electric field mode is equipped with pixel electrodes and common electrodes formed in an array substrate, respectively. Liquid crystal molecules are switched by the lateral electric field substantially in parallel with the principal surface of the array substrate.
On the other hand, another technique is also proposed, in which a double layer pixel electrode is arranged between adjacent source lines to easy influence by leaked electric field from a source line.